The ADS-B Beacon with Low Altitude Surveillance is intended for managers of tall structures such as
buildings, radio towers, power lines, tethered balloons etc. for implementers of the NASA UAS Traffic Managment (UTM) system
and for operators of airport service vehicles and emergency vehicles.
These customers all belong to category set C as illustrated below.
"0: limited category information - surface obstruction"
"1: surface vehicle - emergency vehicle"
"2: surface vehicle - service vehicle"
"3: point obstacle (includes tethered balloons)"
"4: cluster obstacle"
"5: line obstacle"
Benefit To Customer
For managers of tall structures, placing an ADS-B beacon on top of the structure provides cooperative aircraft the means to
sense and avoid the structure. This can be particularly important for Unmanned Aerial Systems (UAS) operating beyond visual
line of sight (BVLoS). For implementors of the NASA UAS Traffic Management (UTM) system low altitude surveillance becomes possible in
urban canyons and in areas where terrain masks low-altitude vehicles from radar coverage.
Effective Radiated Power (ERP): one watt
Baseline is ADS-B Lite
Mode S Transponder with 1090 MHz Extended Squitter: included
The ADS-B Lite "back end" determines the appropriate response to an IFF interrogation and encodes the extended squitter messages for ADS-B "out".
Identification Friend or Foe (IFF): included
In remote areas where radar is masked by terrain IFF interrogates surrounding low altitude traffic with a one watt transmitter.
The time of arrival of the transponder replies at different receiving sites are then used to determine the location
of both cooperative (ADS-B) and non-cooperative (transponder only) traffic.
Although surface vehicles may move, fixed obstacles such as buildings, towers and such do not.
However, for multi-static radar and multilateration to work, multiple receivers must be synchronized
to the same time reference. That reference is given by GPS and is accurate to a few tens of nanoseconds.